An epidemic of multidrug-resistant (MDR) bacterial infections continues to plague global and US health care, and with few new drugs making it to market from a diminished pipeline, there is an unmet medical need for new therapeutics to treat drug-resistant infections. Furthermore, effective therapies are urgently needed to address ongoing public health and biosecurity concerns that high-threat select agent bacteria can be engineered to become resistant to all currently available antibiotics. The central hypotheses of this Center application are that seeking novel compounds directly targeting MDR Gram-positive and Gram-negative pathogens has the greatest probability of finding new antibiotics, and that concerted collaboration among academic institutions and industry will accelerate the antibiotic drug discovery process. The mission of the Center is to support early drug discovery efforts, including target validation, chemical lead identification, structure-activity relationship analysis pharmacokinetics and in vivo therapeutic efficacy, and thereby develop optimized chemical Leads that are suitable candidates for preclinical evaluation. We propose in aims 1 and 2 to explore novel classes of compounds against proven targets with broad spectrum application, RNA polymerase and DNA gyrase; 3) characterize novel compounds against mycolic acid biosynthesis in Mycobacterium tuberculosis; 4) develop untapped environmentally-derived novel peptides, as a source for new antibiotics; and 5) use computational Bayesian modeling to accelerate antibacterial discovery. Critical success factors are the strength of Project Leaders with innovative drug discovery programs, and the inclusion of Trius Therapeutics, a biopharmaceutical company focused on antibiotic development. The Center is supported by an integrated infrastructure of support cores for compound optimization and access to the UMDNJ Regional Biocontainment Lab for pathogen studies. The overall program will be guided by David Perlin, an accomplished translational researcher and administrator, a Scientific Advisory Committee including members of Pharma, and a solid operations and management team that can effectively manage large translational research programs and promote licensing opportunities.